The unit of a magnetic field is :

1. NAm
2. Nm A^-1
3. N^-1mA
4. Nm^-1A^-1

In fleming's left hand rule, the forefinger indicates the direction of :

1. force
2. current
3. motion
4. magnetic field

The magnitude of force acting on a current carrying wire placed in a magnetic field in a direction perpendicular to its length depends on :

1. The current flowing in the wire
2. The strength of the magnetic field
3. The length of the wire
4. all of the above

The speed of rotation of coil can be increased by :

1. decreasing the strength of the magnetic field
2. decreasing the area of the coil
3. increasing the area of the coil
4. decreasing the number of turns in the coil